1. Field of the Invention
This invention relates to an improvement of a fishing spinning reel having an oscillate mechanism.
2. Description of the Related Art
As is well known in the art, in general a fishing spinning reel is designed as follows: A semi-circular bail is coupled through bail supporting members to the ends of a pair of supporting arms provided on a rotor in such a manner that it is swingable to take a fishing line take-up position and a fishing line let-out position. When, with the bail set at the fishing line let-out position, terminal tackles which include the hook, the float, etc. are thrown, the fishing line is spirally let out from the spool. On the other hand, when, with the bail set at the fishing line take-up position, the rotor is turned with the handle to take up the fishing line, the fishing line is wound on the spool which reciprocates in association with the rotation of the rotor.
An example of a conventional mechanism for moving the spool back and forth (reciprocate) in association with the rotation of the rotor is an oscillate mechanism as shown in FIG. 19.
The oscillate mechanism 1 is designed as follows: A handle shaft 3 has a gear 5 engages with an idle gear 7. A protrusion 9 is provided on the periphery of one side surface of the idle gear 7. On the other hand, an oscillate slider 13 having an oscillate groove 11, which is engaged with the protrusion 9, is secured to the rear end portion of a spool shaft 15. As shown in FIG. 19, heretofore, the oscillate groove 11 extended vertically, being perpendicular to the spool shaft 15, and a spool 17 was secured to the end of the spool shaft 15.
In FIG. 19, reference numeral 19 designates a pinion at the rear end of the rotor 21. The spool shaft 15 is inserted into the pinion 19 in such a manner that it is movable back and forth with respect to a reel body 23.
The pinion 19 is engages with a drive gear 25 fixedly mounted on the handle shaft 3. When, in order to take up the fishing line, the rotor 21 is turned through the drive gear 25 and the pinion 19 with a handle (not shown), the idle gear 7 also turns. As a result, the protrusion 9 moves on a circular orbit, and accordingly the oscillate slide 13 moves the spool shaft 15 along the oscillate groove 11 back and forth, and therefore the spool 17 is reciprocated in the same direction.
However, the above-described oscillate mechanism 1 suffers from the following difficulties: since the protrusion 9 moves on the circular orbit as was described above when the reciprocation of the spool 17 switches with respect to the rotation of a predetermined angle of the idle gear 7, the amount of displacement (movement) of the oscillate slider 13 is decreased and the spool 17 is decelerated. Therefore, the fishing line is wound more on the front end portion and the rear end portion of the fishing line winding surface of the spool 17 than on the remaining (substantially middle) portion. On the other hand, the speed of the spool is highest substantially at the middle of the reciprocation. Hence, the amount of fishing line wound on the middle of the spool 17 is less. Accordingly, the fishing-line wound surface is sunk at the middle portion of the spool, and raised at both end portions.
The fishing line wound on both end portions of the spool is liable to collapse as a result, resisting the fishing-line which is being let out of the spool. This fact makes it difficult to sufficiently throw the terminal tackles.
In order to increase the oscillate store to increase the line winding capacity, the oscillate mechanism 1, may be modified by increasing diameter of the idle gear 7 and the protrusion 9 is provided-at the periphery thereof, and by lengthening the oscillate groove 11 vertically. However, if the diameter of the idle gear 7 is increased, then the reel body 23 also increases in diameter, which increases the weight of the reel accordingly.
In order to overcome the above-described difficulty, U.S. Pat. No. 5,350,131, and Korean Utility Model Examined Publication No. 92-8122 have disclosed a spinning reel as shown in FIG. 20 in which the oscillate groove 27 is substantially S-shaped. In those spinning reels, the oscillate groove 27 is shaped in correspondence to the locus of movement of the protrusion 9 when it is assumed that the oscillate slider is moved in uniform motion.
However, it is true that the spinning reel shown in FIG. 20 also has the same difficulties as the one shown in FIG. 19.
FIG. 20 is a diagram showing the abutment of the protrusion 9 against the oscillate groove 27 at angular rotation intervals of 30.degree. of the idle gear in the direction of the arrow X, and FIG. 21 shows the line winding positions of the spool 29 in correspondence to the points A' through G' in FIG. 20. In FIG. 20, the point A' corresponds to the rear end of the stroke of the spool 29 shown in FIG. 21, and the point G, to the front end of the stroke of the spool 29.
In the conventional oscillate mechanism in which the oscillator groove 27 is provided at the oscillate slider, because of its structure, the oscillate slider performs a uniform speed motion with an angular width of rotation of 90.degree. between the points D' and G' and between the points J' and A'. However, when the reciprocation of the spool is switched at the F' through H' points and-at the L' through B' points, with respect to the rotation of a predetermined angle of the idle gear, the amount of displacement of the oscillate slider is smaller than in the other regions. Hence, as shown in FIG. 21, the fishing line is wound more in the vicinity of the front and rear end portions (the points a' and g') of the line winding surface 31 than in the other portion.
Also, between the points A' and C', and between the points G' and I', the speed of the oscillate slider gradually increases, while at the points N' and P', the middle of the line winding surface 31, the speed of the oscillate slider is highest. Therefore, between the points C' and D' and between I' and J', the amount of displacement of the oscillate slider is greatest. Therefore, as was described above, in the reciprocation of the spool 29, the highest speed points N' and P' are coincident with each other. Hence, as shown in FIG. 21, the amount of winding of the fishing line at the middle of the line winding surface is smaller.
Hence, it is true that the above-described prior art is improved in line winding condition when compared with the prior art shown in FIG. 19. However, as shown in FIG. 21, the difficulty is not eliminated yet that the line-wound surface 31 is inflated at the front and rear end portions, and recessed at the middle portion.
On the other hand, Japanese Patent Unexamined Publication No. Hei. 8-154543 has disclosed an oscillate mechanism 39 in which, as shown in FIG. 22, an oscillate groove 35 of an oscillate slider 33 is inclined in a front-to-rear direction of a spool shaft 37.
In the oscillate mechanism 39, the stroke of oscillation can be increased without an increment of the diameter of an idle gear 41. Hence, for given size reel the oscillate mechanism 39 provides a larger winding capacity of a fishing line than the above-described prior arts. However, the oscillate mechanism 39 again suffers from the difficulty that, when the fishing line is wound up on the spool, the line wound surface is inflated at the front and end portions, and recessed at the middle portion. That is, even with the oscillate mechanism 39, the line winding state is not improved at all.